Choosing The Right Engine

[Hterrygqt]

Gday everyone, I have a 99 patrol wagon with a blown RD28tdi, as a rb motor is a near on stright in conversion i plan to put in a RB motor.

Now iam looking for torque being a 4wd , but ive had people say use the RB25det, RB30et or a custom RB30/25det. Now since all you boys know your skyline id thort id ask wat is the best engine?

Thanks alot

Hayden

[GTR260]

25/30 or 26/30 would be best, I have a rb30 for sale if u want a new bottom end, just bolt on whatever head u choose to use,

The only issue is I don't think you can use a old model engine in a later model car due to emissions reasons

Edited January 27, 2013 by GTR260

[blind_elk]

If you are after torque, then you should stick with the diesel.

[GTSBoy]

Yuh. Build the diesel. Add more boost and LPG.

[Hterrygqt]

As the TD42 diesel engine rebuilt, conversion and bolt ons such and modded injector pump, modded turbo is about $25,000. Now the engine i have is a 2.8 diesel and is a slug and has same mounts and gearbox as a RB motor it makes sence to save money and put one in, iam not after 800nm plus all iam after is the most torque out of the RB series, its a simple conversion aswell .

Cheers

Hayden

[GTSBoy]

Petrol Patrols drink the juice and offer no torque compared to the diesel options.

[AngryRB]

Petrol Patrols drink the juice and offer no torque compared to the diesel options.

wouldnt an rb30et with a gt30 put out more torque than a 2.8 diesel turbo? considering the gears are so short, or is the comp ratio of a diesel the difference? just interested to know..

Edited January 27, 2013 by AngryRBGTX

[Hterrygqt]

The 2.8 only puts down around 220nm standard, the turbo starts to spool at about 2200rpm and is on full song at near 3000rpm , ive read the RB30/25 can have 550nm may be just a little later in the rpm. The 2.8 diesel revs at 3000rpm doing 100kms gets about 400kms/80ltrs it is underpowered it only makes sence to replace the motor with a RB series motor

[GTSBoy]

An RB30 with big turbo would put out a lot of torque, but it would do it from 3000rpm up. Diesels pump out the torque from right off idle. It is the comp ratio and the unthrottled air flow path that make diesels have that characteristic. Add a turbo to a diesel (because they really are gutless* without them) and they start to become the best choice for any 4WD thingo. Add LPG into the inlet manifold along with that boost and they start to become a rocketship, and cheap to run too.

*gutless as in, no power. They still have decent off idle torque when NA.

[WMDC35]

there's a few y60s running rbs round here, people seem to be pretty happy with results

[steve200b]

I have done the same thing and went with a Rb30et gt3076r, 444cc injectors and a Nistune ecu. alot better than a standard RD28, mine is a GQ so a Rb30 was standard I assume you have a GU so you will need engineers for the motor and you will need to comply with the emissions regulations.

[The Bogan]

Drop a fresh GM V8 in, will be lighter and use less fuel than a boosted RB.

RBs are pretty old technology now, the newer GM motors put out good torque right from the bottom, need minimal modifications to get decent power, and are reliable.

Most likely cheaper to.

[Tai1or Made]

12A.

[The Bogan]

138 grey motor has more tourqe than a 12A

[GTSBoy]

OK, so 138 grey it is.

/thread

[Rolls]

rb30et would be a pretty simple swap, or rb25det following that. Are there any good forums for patrols? there are probably a shitload of better diesel options you could put in there that may/may not be less work.

[RRob]

Clearly most of you have not driven a RD28. Comparable to a RB20.

[Hterrygqt]

Thankyou RROB , the RD28 diesel engine is a POS at the best of times, like i said a TD42 conversion with bolt ons ( turbo , pump , ic etc) is around $25,000. Ls1 conversion is $7,000 just for the conversion kit, then needs the motor then a rebuild and i need a bigger gbox as i have the weaker one that will not work with Marks 4wd conversions kit, Like ive said a RB will bolt into my gearbox and engine mounts , all it needs is wiring ( just like TD42 and LS1 would ) fuel consumption would be near on the same as a ls1 but with the ability to change boost to save abit of fuel. Now i am after as much torque as i can get from a RB series engine . All i need is advice on witch setup to use to get torque and off boost driveability. Thankyou

[RRob]

Just did my brothers patrol (GQ), although his was already RB30. We simply bashed a twin cam head on his existing bottom end, EFI'd it and bolted on a HKS 2540 for good measure. Fuel consumption is now better, it makes 313HP at the rears and can now tow a boat at 110 comfortably!

[GTSBoy]

Please tell me you know all about LPG fumigation and don't think it will help.